7pm, Oxford ring road
Even world champions get stuck in traffic jams, and Senna drops the NSX's window down as the big Honda slowly lines up behind at least a mile of traffic. "Oh nice!" he says, his English as soft and clear as a choirboy. "Looks really bad," he concludes.
Still, it's as good an opportunity as any to talk to Senna and he's happy to chat about the automatic NSX, his own manual version in Portugal, the similar one he hopes to have in Brazil, and the Golf GTI and the Mercedes 300TE it will join there.
"You know, I basically like driving, so long as it's more sportive than a classic and not a soft car that's slow," he says. He's a big fan of the NSX, and not just because Honda pays his wages or because he's likely to open the first Brazilian Honda dealership when he retires.
"It's not a Ferrari, it's not a Porsche, it's a Honda. I drive many different makes of cars. I like this car for everything it's not. It's not the most powerful sports car, but it has enough power for you to enjoy on the roads. You cannot have a lot of power to use on the roads anyway or you may become a big danger for everyone else." To prove the point, Senna floors the throttle and we race into the gap that has opened as we chatted.
Senna's getting a bit restless in the jam, although he takes the waving, smiling and shouting from passing school kids in good humour. I put it to him that the NSX is a bit of a soft touch for the best driver in F1 today.
"I don't want an uncomfortable car or a noisy car; I want a real automobile without the characteristics of high-performance sports cars. Normally a sports car you cannot drive every day because of the noise and all the uncomfortable things that come with it. This car you can because the fundamental concept is a car to be enjoyed and driven around in any conditions."
7.30pm, Manoir aux Quat' Saisons, Great Milton, Oxfordshire
We're not going to break any Oxford/Great Milton records. Senna, unlike a lot of his colleagues in F1, doesn't drive like a loony on public roads. Besides, we've got Milton Senna, Ayrton's father, behind us in a Honda Legend.
Senna has stayed at Raymond Blanc's Manoir aux Quat' Saisons before and the staff show restrained delight as he arrives, the girls blushing, the boys trying to be cool. They all get a wave and a smile from the man.
Ayrton and his father dine alone. He eats well but drinks only Evian water. He's in his £220-a-night bed well before midnight.
Monday 24 June 1991
Senna rises early, exercises, runs and eats breakfast. Milton sits quietly beside his youngest son as he's driven to Silverstone.
10am, Silverstone – Alan Henry reports
A depressing wall of rain hangs over the circuit like a wet blanket. Senna changes into overalls and confers with McLaren team engineers and Honda technicians.
Engine testing is the main priority for Senna following his disappointing run to third place in the Mexican Grand Prix. Honda needs to extract more power from its RA121E V12 engine. Senna has been aware of this since pre-season testing and he's anxious that they do not underestimate the task ahead.
1pm, Marlboro McLaren motorhome
Break for lunch. The weather has not been good enough to reach any conclusions. The first of the latest specification 3 engines is promised for his evaluation the following day.
Journalists sidle up to him, canvassing his views on a wide variety of subjects. He chats openly about the new layout of the Silverstone circuit: "It is not so comfortable in places. There are some bumps that need ironing out. It still needs to be improved for safety reasons."
How did he feel about McLaren falling off the pace in Canada and Mexico? "We didn't really have any problems in Mexico," he replies, "but we were just not good enough to beat Williams. In Canada we had no chance to compete with them, and although we were closer in Mexico we just couldn't match their performance.
"Fortunately we won four races at the start of the year, which has given us breathing space for the engineers to make progress. The biggest problem is engine performance, but Honda is committed to making radical changes to the engine specification to get back on terms with Williams and Ferrari."
4.45pm, pit lane
Getting the world champion to drive our road testers around the new Silverstone in their favourite supercar took some planning. But now Ayrton Senna, the Honda NSX and the circuit were all ours. It was so wet that a boat would have been more appropriate, but Senna didn't seem to mind. With barely concealed delight, deputy road test editor Andrew Frankel climbs into the NSX's passenger seat as the world champion plays chauffeur for a memorable 20 minutes.
5pm, Silverstone – Andrew Frankel reports
It was only on the last sublime lap, where the car's speed and the angle of the oncoming corner were so utterly impossible to reconcile, that I forgot who was at the wheel.
As Bridge hove into view after a terrifying right-hand flick at the end of Farm Straight, Senna had the Honda howling past 100mph. I was awestruck but not concerned. He had done as much on the last lap and I could still remember where he would brake, shed 30mph and guide the nose of the NSX to the apex and beyond. But it seemed Senna had forgotten.
As we sailed past the point of no return at unabated speed, my voice, which had tried to record every detail of this ultimate experience for posterity, fell silent on the tape recorder. The time for talking, it appeared, was over. I started to curse that devil within me that had sneakily switched out the Honda's traction control before Senna climbed aboard.
Then I remembered the man sitting just an armrest away. The man with more pole positions than anyone else in history and more grand prix victories than all but the considerably older Alain Prost; the man treated with more respect and trepidation than any other in motor racing. I was about to find out why. In an instant my faith returned, and although I knew that not even Ayrton Senna could get the NSX through that corner at that speed, I also knew that, somehow, it would be all right.
He twisted the wheel into the corner and then he braked. As he did so, the rear of the Honda flew into its inevitable, almighty slide that said unequivocally: "I am taking you and Mr Senna off this track and I'm not coming back."
Mr Senna, however, had other ideas and simply pressed the pause button. This facility, denied to you and me, allows the finest drivers in the world to slow down the action to a more manageable speed and, in the case of a fast-moving NSX tail, stop it altogether. With a twist of opposite lock and just the right amount of throttle, it slid no further. It didn't come back; there was no need. It just hung there in a state of suspended animation, a few degrees off line, waiting until the nose kissed the rumble strip on the apex before snapping straight as we swept back towards the pits.
I don't know how fast the NSX took that evil, drenched corner, but by the time I had got a grip on myself and my eyes back on the speedo needle, it was hovering above 90. Senna remained expressionless, and if he reads this I doubt he will even remember.
It's something I will never forget. But my laps with Senna weren't all like that. On the contrary: on the first lap the world champion trundled through corners at speeds I could match, chatting away, eyes shining. Patiently, he took time to talk me through the differences between the old circuit and the new.
Apologising for not having completed enough laps to make a proper evaluation‚ he nevertheless seemed to have committed the entire track to memory in considerable detail. As we enter Copse, the first corner past the pits, he observes: "You turn in earlier here and it's much faster now. It used to be smooth but now it's very bumpy."
Beyond the next short straight and Maggotts curve, the track jinks left, right, left through Becketts and Chapel. In his McLaren, Senna takes all of these in fourth, which he says is "quite fast". Clearly he is not a man prone to exaggeration.
Even so, "you exit slower than before and that lowers the speed you can achieve down Hangar Straight." As we exit Chapel onto the never-ending strip of tarmac, Senna says with considerable relish: "You need pure power down here," as if to recall pointedly the traditional overwhelming superiority of his Mclaren-Honda in this area, so notable by its absence this season.
I suggest that the right-hander at Stowe looks much the same as before. "You're right to a point. Everything is exactly the same until here, it tightens."
Simultaneously he hauls the NSX on to the new line and we head off to Vale, a sharp left which is governed by handling and driveability. "It's very tight and that makes the next corner [Club] slow. You used to be in fifth gear; now you start in third and go through in fourth. Speed down the straight to Abbey and beyond is governed by how fast you can leave Club and it's slower than before. You still go through [Abbey] in top but you use shorter gearing than before which reduces your maximum speed".
Bridge sees Senna digging deeper into his understatement sack, describing it as "a new corner taken in fifth gear, which is quite fast." Even though I know that means 150mph or more. Then the circuit slows you down through the increasingly tight Priory, Brooklands and Luffield, by which stage speeds are so low that it's impossible to approach the once notorious Woodcote fast enough to make a corner out of it.
Professional to a fault, Senna refuses to compare the new circuit to the old until he has learned more about it. However, he does agree that changes needed to be made: "I liked to drive the old circuit but it was dangerous: didn't feel safe at all as it was so fast."
Still, he is not without fond memories of what was then the fastest grand prix track in the world and says that in one way at least, the new track fails to meet the standards of the old: "One thing that always gave Silverstone a clear identity was its smooth surface, but in the few laps I did today I found it very bumpy."
It wasn't until we were passing the pits that Senna turned up the flame. You only need to look at him to see when Senna gets serious. The talk stopped, his face fixed and where his eyes once twinkled now they blazed, dead ahead as the NSX charged back towards Copse.
As I watched, I thought I might see something that at least hints at what makes him so extraordinary. But, save for his steel expression, I found no help. He sits in the car like your driving instructor told you to, with his arms slightly bent. He leaves the backrest where I set it and moves the squab closer to the pedals so his legs are at a similar stretch to his arms. All textbook stuff, he even holds the wheel at ten to two.
Where he differs from us and, for all I know, everyone else in the world, is in the way he controls the car through corners. Even if you shut off the sight of the circuit flashing by and just concentrate on the way he moves his hands and feet you would still know, without a doubt, that you were in the presence of a master. To Senna the steering and the throttle could just as well be one control. He never moves one without the appropriate adjustment to the other. Even as we slithered ludicrously sideways out of Copse, his hands were so calm and graceful they almost looked slow.
If no one told you he had one in Portugal and another on order in Brazil, it would still be clear that Senna loves the NSX.
But this is one of the first with power steering and automatic transmission in Britain, and as we bowl down Hangar straight at 125mph, the screaming V6 bouncing off its rev limiter as Senna changes manually, he expresses reservations: "The power steering suits the car but automatic transmission is much more personal and I don't think it's a good thing in this car. In other cars and in traffic I like automatic gears, but in the NSX, a manual gearbox is the one to have."
As he speaks he flicks the gear lever back into third, leaves his hand there and aims the NSX at Stowe. We exit broadside at 80mph, a wall of spray pluming behind the Honda as Senna plies an inch-perfect line, just one hand on the wheel.
That's the one moment of my afternoon with Ayrton Senna I'd bottle if I could. Of course, he continued to astonish on every corner of the remaining laps, but nothing, not even that final, awesome moment at Bridge, put the difference between Senna and other decent drivers in sharper perspective.
It's not just that he can do things with a car that, had I not witnessed them first-hand, I would not have believed possible. He's better than that. He does them without trying.
Early evening, M40
Driving to London, Senna's Honda Legend is pulled up for speeding. Reports of his speed vary. One estimate is 130mph. He is let off with a caution.
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